184 μW ultrasonic on–off keying/amplitude-shift keying demodulator for downlink communication in deep implanted medical devices

• Published in: Electronics letters 2016-04, Vol.52 (7), p.502-504
• Main Authors: Mazzilli, F, Dehollain, C
• Format: Article
• Language: English
• Subjects: amplitude shift keying; biomedical communication; biomedical electronics; Biomedical technology; bit rate 50 kbit/s; CMOS integrated circuits; CMOS integrated ultrasonic demodulator; data signals; deep implanted medical devices; demodulators; downlink communication; downlink data transmission; envelope detector circuit; external base station; frequency 1 MHz; hysteresis comparator; low‐noise amplifier; offset cancellation circuit; power 184 muW; prosthetics; size 0.18 mum; ultrasonic devices; ultrasonic on‐off keying‐amplitude‐shift keying demodulator; variable‐gain‐amplifiers; voltage 1.5 V
• ISSN: 0013-5194; 1350-911X; 1350-911X
• DOI: 10.1049/el.2015.4267

An ultrasonic on–off keying/amplitude-shift keying demodulator using standard 0.18 μm CMOS technology is proposed, intended for recovering the identification number of an implanted medical device transmitted from an external base station. The CMOS integrated ultrasonic demodulator consists of a low-noise amplifier, variable-gain-amplifiers, an offset cancellation circuit, an envelope detector circuit and a hysteresis comparator. Downlink data transmission of 50 kb/s data signals in the 1 MHz band is successfully demonstrated, the power consumption is about 184 μW from a 1.5 V supply. The architecture is described, and the measurements performed confirm the theoretical result.